peter's square for pope benedict's final audience this morning, cheering and waving signs that read "thank you" in italian. anne thompson is live for us at the vatican. and anne, i know the pope gave a reason for why he's leaving. what did he share with the crowd? >> reporter: well, he told them, chuck, it was a very personal address during his final papal audience. usually those sermons are a lesson on religion, but he spoke quite eloquently about his eight years as pontiff and why he was stepping down. he said his eight years had been filled with joy and difficulty and he said at some times, he felt like the lord was sleeping during his eight years. he acknowledged, again, that the reason that he was stepping down was because of age. he fired back at his critics, as much as a pope will fire back, saying that, you know, the critics who said that the pope should not come down from the cross, he said, there are different ways to serve on the cross and that the life that he has chosen of prayer and meditation, that will begin thursday night, that is another way to serve the church. agai